Catholics opposed to President Obama attending the annual Alfred E. Smith charity dinner in New York have started an online petition urging Cardinal Timothy Dolan to withdraw his invitation to the president.

“If Cardinal John O’Connor didn’t invite pro-abort Bill Clinton in 1996, and if Cardinal Egan didn’t invite pro-abort John Kerry in 2004, then on what grounds could your Eminence find to invite Obama in 2012?” the petition asks Cardinal Dolan. The opponents, who refer to the president’s invitation as “scandal,” said Mr. Obama “has proven handily and has worked arduously since 2009 to act in defiance of our fundamental moral principles.”

As of Wednesday afternoon, more than 1,200 people had signed the petition at www.alsmithscandal.com.

“Please dis-invite President Obama,” wrote a petitioner who identified himself as Martin Soy. “Do not give him a platform to campaign in favor of the Culture of Death.”

The New York archdiocese surprised some people with its invitation of the president, whose relationship with the Catholic Church has been strained, particularly by the administration’s mandate of contraception coverage this year in the new federal health care law and the president’s support for same-sex marriage.

Bishops have called the health care mandate a threat to the church’s mission and to religious freedom.

Presumptive Republican presidential nominee Mitt Romney also has received an invitation to this year’s dinner, which will be held at the Waldorf-Astoria hotel in October. Both Mr. Obama and Mr. Romney reportedly have accepted the invitations, meaning it would be one of the rare occasions other than the presidential debates in which they appear on the same stage.

The annual white-tie affair draws a wealthy audience and is a big fundraiser for Catholic charities. Politicians who speak at the event typically end up roasting each other and themselves; during the 2000 campaign, Republican George W. Bush famously told the well-heeled crowd, “Some people call you the elite; I call you my base.”

Presidential candidates often, though not always, receive invitations to the dinner every four years. As the petition notes, Mr. Clinton and Sen. Bob Dole were not invited in 1996, nor were Mr. Kerry and President George W. Bush in 2004.

In 2008, Mr. Obama and Sen. John McCain, the Republican presidential nominee, both attended the dinner.

Mr. Obama needled Mr. McCain about his age and made jokes about his own middle name, Hussein, telling the audience: “I got my middle name from somebody who obviously didn’t think I would ever run for president.”

The Rev. Frank Pavone, head of Priests for Life, a group based in New York, said it’s not appropriate for Mr. Obama to attend the dinner this year.

“I’m all in favor of protocol and understand the difference between respecting the president’s policies vs. respecting his office,” he said in a statement. “But there comes a time when the polite putting aside of differences for a while amounts to scandal.”

Cardinal Dolan has been critical of the Obama administration, saying the health care mandate is “strangling” the church’s mission. More than 40 religious organizations, including the New York archdiocese, are suing the administration in federal court to block the mandate.

But Joseph Zwilling, a spokesman for the archdiocese, has said the dinner is “an evening to put politics aside and come together in a spirit of civility.”

Among the luminaries who have spoken at the dinner in the 67 years since it began are presidents from Dwight Eisenhower to Ronald Reagan, generals, entertainers such as Bob Hope, captains of industry and even Winston Churchill, who spoke to the crowd in 1947 via trans-Atlantic telephone.

Mr. Smith, a former governor of New York, was the first Catholic candidate to run for president on a major-party ticket in 1928. After his death in 1944, the New York archdiocese began to hold the annual dinners to benefit the Alfred E. Smith Memorial Foundation.